If you really
are serious about saving your lead, make yourself a "bullet bucket" like I did. It's portable, cheap, and easy.
Go to Home Depot. Buy two of their $2.50 buckets and lids. Go to the garden area and buy a cheap bag of chipped rubber mulch.
Cut out a piece of 3/4" thick plywood to fit into the bottom of a bucket. Fill a bucket up with the rubber mulch. Stand on it to pack it in tightly. Snap the lid on.
To use, set one bucket on it's mouth, and then lay the other bucket on top of it. Drive a tent stake in the ground on either side and use a ratcheting tie-down to secure the top bucket to the bottom bucket.
Staple your target to the cover of the bucket.
For revolvers with target loads (20 grains powder) your bullets will never make it to the plywood. For muskets, they will. So I put 4 pieces of .03" thick mild steel sheet metal over the plywood. It soaks up the last of the energy.
You might have the occasional bullet shoot out the side of the bucket. Just slap a piece of duct tape over the hole and keep going. You can likewise stretch out the life of the lid the same way. Eventually, you'll have to buy a new lid.
Here are some pictures:
At nearly $2 a pound for pure lead, this really stretches my target shooting buck.